153 
Larva of a Dipterous Insect. 
the spring of 1836, and it was not till the summer and autumn 
of that year that the larvae were observed in the motions. They 
then passed off in very large quantities on different occasions, the 
discharge continuing at intervals for several months. According 
to the patient’s own statement, the chamber-vessel was sometimes 
half full of these animals ; at other times they were mixed with 
the stools. He thinks that altogether the quantity evacuated 
must have amounted to several quarts. The larvae were all 
nearly of equal size, and, when first passed, quite alive, moving 
with great activity. The patient is not aware of having voided 
any thing of the kind before. Since the discharge ceased, his 
health has improved, but it is by no means perfectly re-esta- 
blished ; and he is fully impressed with the belief that at the 
present time (March, 1837) more larvae are still in the stomach 
and intestines. 
Immediately on examining the above larvae, specimens of which 
were procured by Dr. Haviland, and submitted to my inspection, I 
formed the opinion that they were those of some dipterous insect ; 
and, from their possessing branchial-like appendages, that the 
species was one which, during its first state, was, if not decidedly 
aquatic, at least an inhabitant of moist places. This opinion was 
afterwards confirmed by Mr. Hope, to whom I exhibited the spe- 
cimens when in London last February. The same gentleman drew 
my attention to a case already recorded by Dr. Bateman,* in 
which, judging from his annexed figures more than from his slight 
and evidently inaccurate description, there was reason to believe 
the very same larvae had been observed under similar circum- 
stances. In fact, Dr. Bateman mentions two instances : one, in 
which a considerable number were ejected from the stomach of a 
labouring man at Norwich ; another, in which they were found 
intermixed with the alvine discharge of a patient, who believed 
them to have been evacuated from his bowels, although the sur- 
geon who attended him was doubtful whether they might not have 
been generated in the water-closet. Those obtained in the former 
of these instances, and which, as in the case now before us, were 
alive and moving for some time after they had been discharged, 
were considered by Dr. Bateman (on the authority of Mr. Bracy 
Clark) as the larvae of the Musca domestica minor of De Geer.j' 
which is synonymous with the Musca stercoraria of Swammerdam, 
by whom the larva is figured, under the name of Vermiculus latri- 
* Edinb. Med. and Surg. Journ. vol. vii. p. 41. 
t Hist, des Ins. tom. vi. p. 26. 5. Dr. Bateman states, however, that De Geer 
lias figured both the fly and its larva, which I do not find to be the case. 
N 
